Molding and gluing press



June 4, 1946. R. E. GLM/,N 2,401,299

' MOLDING AND GLUING PRESS Filed Oct. 5, 1942 25' Vn/wrm? ggg W $0,502/ E. Gia-fn Patented June 4, 1946 MOLDING AND GLUIN G PRESS Robert E. Gravin, Bristol, Tenn., assigner to Universal Moulded Products Corporation, Bristol, Va., a corporation of Delaware Application October 3, 1942, Serial No. 460,716

- 3 Claims. 1

This invention relates to improved apparatus for shaping or molding and gluing together laminations of material, as in the manufacture of plywood structures-for the building of boats, airplanes, and the like.

It is well known that a plurality of laminations of thin wood veneer may be shaped or molded Aabout a removable mold, and that by activating a thermo-responsive plastic adhesive interposed between the laminations the several plies may be bonded together to form a molded plywood structure that, will retain indefinitely the form so given to it.

The present invention relates to improved ap. paratus for rapidly and conveniently carrying out the molding and gluing operations incident to the production of such molded.v plywood structures.

A preferred embodiment of the invention is -shown in the accompanying drawing, in which:

Figure 1 is a longitudinal sectional view through the molding and gluing press in accordance with this invention;

Figure 2 is a sectional view on the line 2-2 in Fig. l, showing no pressure applied;

Figure 3 is a sectional view on the line 3--3 in Fig. 1, showing pressure being applied; and

Figure 4 is a detail view of the door 'sealing means.

As shown in Figs. 1-3, the improved molding and gluing press in accordance with this invention comprises a chamber formed by a generally semi-cylindrical outer shell I and a plane oor 3, closed at one end by the wall 5 and adapted to be closed at the opposite end by a door 1.

The floor 3 is stiifened and strengthened by a plurality of channel beams 9, while the rear wall 5 and door 'l are strengthened by a plurality of ribs II. The door is designed to be retained in place by the engagement of its inwardly opening peripheral channel I3 with the bead I5 secured to the forward edge of the shell I, and by the engagement of its lower edge I'l in the slot I9. A gasket 2| positioned in a recess in the rear face of the bead I5 (Fig. 4) serves to seal the door.

The chamber formed-within the shell I `is divided into two sections, 23a and 23h, by a heavy, impervious, exible membrane 25 of rubber or similar material. The membrane 25 is tightly clamped to the shell I and the rear Wall 3 by means of bands 2I and bolts 29, which extend along both sides of the shell I and the end wall 5 and is secured at the front of the chamber by being clamped between the semi-circular band 3l and a flange of an angle iron 33 welded to the inner surface of the shell I.

which the membrane is clamped extend from the band `2l at one side of the shell across the semicircular top to the band 2'I at the other side of the shell. The chamber 23a above the membrane 25 is thus entirely closed by`the walls I and 5 and the membrane itself; while access may be had to the chamber 23b'below the membrane 25 by removal of the door l.

Positioned within the chamber 23a is a heater 35, through which steam may be circulated, as

-by conduits 3l, 39. A plurality of conduits 4I lead directly Into chamber 23a, which thus may -be connected to water, compressed air, vacuum lines, etc.A Positioned within the chamber 23h is an impermeable flexible bag 43, of rubber or similar material, the interior of which communi- Cates with conduit 45.

In molding plywood, a plurality of plies of wood veneer 4l and interposed layers of adhesive are placed about and loosely conformed to a hollow mold or mandrel 44, of wood or metal. The mandrel 44 with the wood plies positioned upon it -is then placed within the chamber 23h upon the floor 3. A vacuum may be drawn in chamber 23a to raise the membrane 25 up out of the way during this operation, as shown in Fig. 2. The mandrel 44 is so positioned that the bag 43 is covered thereby. 'Ihe door 1 is then lowered into position to close the chamber, and air or other fluid under pressure is admitted to the chamber 23a, and to the bag 43.

The blanket 25 is thus forced down upon the wood veneer (Fig. 3), causing it to conform exactly to the. shape of the mandrel, which is enabled to withstand the pressure 'exerted upon it because of the equal pressure exerted by the fluid in the bag 43. Heat required to activate the adhesive may be supplied from heater 35, or

heated air, steam, or hot water may be admitted to chamber 23a and bag 43.

When the molding operation is complete (the temperature, pressure, and time factors for proper molding are known to the art), the chamber 23a and the bag 43 will be evacuated, the door 1 lifted, and the mold 44 and finished plywood structure removed.

It will be appreciated that this invention is not,-

meable membrane extending generally i lengthwise within said container and being secured at itsv lateral edges to the container above the bottom throughout the entire length of the edges, thereby forming within the container two chambers, the lower of which is accessible through the open end of the container, a closure for the open endgof said containenvuid pressure and vacuum'connections, respectively, through the container wall to the upper chamber of said container, a hollow mandrel in said lower chamber upon which material to be molded is positioned, a iiexible, impermeable bag located within the mandrel, and a fluid pressure connection with the interior of the bag.

2. Apparatus for molding and gluing comprising an open-ended container, a ilexible,limper meable membrane extending generally lengthwise within said container and being secured at its lateral edges to the side wall of the container and at its rear edge to the rear wall thereof, said membrane also extending upwardly adjacent the forward, open end of said container and being secured at its edge to the container wall from one side of the container across the top to the other side of the container, thereby forming within the container two chambers, the lower of which is accessible through the open end of said container; a closure for the open end of said container, fluid pressure connection through the Vcontainer wall to the upper chamber of said container,i a hollow mandrel in said lower chamber, a flexible, impermeable bag located within the mandrel and a fluid pressure connection with the interior of said bag.

3. Apparatus for molding and gluing comprising an open-ended container, a flexible, impermeable membrane extending generally lengthwise within said container and being secured at its lateral edges to the side wall of the container and at its rear edge to the rear wall thereof, said membrane also extending, upwardly adjacent the forward, open end of sa'id container and being secured at its edge to the container wall from one side of the container across the top to the other side of the container, thereby forming within the container two chambers, the lower of which is accessible through the open end of said container; a closure for the open end of said ccntainer, a flexible, impermeable bag located in said 

